24. Light pipes, made of optical fibers, can be used to transmit telephone calls and other communication signals how does an optical fiber transmit signals?

a. Light is absorbed and re-emitted by the fiber

b. Light bends and follows the curve of the fiber

c Light is refracted and gains energy as it is transmitted

d. Light is internally reflected in a succession of straight line paths

25. When an object is placed 15 cm from a concave mirror, a real image

three times as large as the object is formed. What is the focal length of the

mirror in centimeters?

a. 45.0 cm

c. 11.25 cm

b. 22.5 cm

d. 5.0 cm

26. A light ray travels from air, to water as shown. Which of the rays is the refracted ray? air water d. C. a. b. 27. A mirror and three letters are arranged as shown. Which of the letter(s) will be seen by the observer at the position shown? a. X only c. Z only b. Y only d. X, Y, and Z X Y Z observer mirror